Tandberg introduced the term DIM, wich in fact is excactly the same as TIM already in 1974.
Also I was lucky enough to have an professor as my teacher when I got my education as an electronics engineer. The very same professor wich trained people behind DOXA, SONOTRON (Later ADYTON), and other HIEND-manufacturers in Norway.
We named him "Professor Balthasar", as he looked just like him.

"The amplifier is fed by symmetrical voltage 19V -44V and +/-26V to the power stage".

I am confused of the use of the term symmetrical voltage of 19V and -44V.
Clearly non-symmetrical as I can see it.

Anyone who can give some good input on this issue?

Hi, I don't have the power supply, sorry.

The original article in the Greek site I think was not accurate (τροφοδοτείται με συμμετρικές τάσεις +19V και -44V). The English translation found in the PDF is more accurate "The amplifier is fed by non symmetrical voltage 19V -44V and +/-26V to the power stage"